there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns – the ones we don’t know we don’t know.

From a statistics point of view the distinction between the three types makes sense: Known knows are fixed parameters in a statistical model, known unknowns are parameters to be estimated while unknown unknowns are confounds that enter the model as ‘noise’. In most cases you hope this noise has a reasonable statistical distribution (e.g., Gaussian and not a black-swan-distribution) and not too correlated with the parameters in the statistical model you are about to estimate.

Now I hear through Mikkel Wallentin that our Danish Minister of State (Prime Minister) Lars Løkke Rasmussen has made an attempt to follow Rumsfeld in the repeated pattern politician poetry in a discussion about tax. A diligent person has put it on YouTube, and my transcription is:

So we have thus chosen to make a system where you must hand in a bit less than you did before. It is what we have chosen, and of course it leads to that those who earns more and hand in a lot and now hand in a bit less – well – they hand in more less than those who earns a bit less and hand in less and thus hand in less less.

I don’t think it was a prepared speech. It seems to lack the epistemological depth of Rumsfeld – and perhaps even logic. But humorous it is, which also Lars Løkke himself seems to realize from around 0:19 in the video.